To evaluate and improve the treatment of clouds and radiation by the climate models of the National Center for Atmospheric Research (NCAR), simulations by the NCAR Community Climate Model version 3 (CCM3), as well as the recently released Community Atmosphere Model version 2 (CAM2), are examined. The Rasch and Kristjánsson prognostic cloud condensate scheme, which is now the standard scheme for...

In this work we describe the second phase in the development of the rapid radiative transfer model (RRTM) (Mlawer et al. 1996), a rapid and accurate radiative transfer model designed for climate applications. The initial phase of RRTM, which uses the correlated-k method for radiative transfer, allowed the calculation of fluxes and cooling rates in the longwave region in clear-sky conditions. Re...

The interaction of shortwave and infrared radiation in the atmosphere with clouds and greenhouse gases represents a complex process that contributes significantly to maintaining earth's climate system. For climate model simulations to become more accurate, it is essential that this process be modeled properly as verified by direct comparisons with observations and with results from a validated ...

South-eastern Australia covers approximately 14% of Australia land mass, and is very important for Australia’s community and economy. In this work, the Weather Research and Forecasting (WRF) regional model was run to simulate the severe drought that happened and then (partially) recovered in this region from 2000 through 2008. The model used the following physics schemes: WRF Single Moment 5-cl...

mineral dust is produced from both natural and anthropogenic sources. dust aerosols can be transported over long distances in the atmosphere. they reduce the incident shortwave radiation to the surface by absorbing and scattering the solar radiation; thereby leading to a cooling effect at the surface and lower tropospheric temperature. on the other hand, by absorption and re-emission of longwav...

The meteorological component of the CSRMC is based on a modified height coordinate prototype version of the nonhydrostatic, compressible Weather and Research and Forecasting (WRF) model. The WRF model is a community model which is being developed in a collaborative effort by the National Center for Atmospheric Research (NCAR), the National Centers for Environmental Prediction (NCEP), the Air Fo...

The Weather Research and Forecasting (WRF) modelling system is developed as a collaborative partnership between the National Center for Atmospheric Research (NCAR), the National Oceanic and Atmospheric Administration (the National Centers for Environmental Prediction (NCEP) and the Forecast Systems Laboratory (FSL)), the Air Force Weather Agency (AFWA), the Naval Research Laboratory, Oklahoma U...

Due to computational expense, the radiation schemes in many weather and climate models are called infrequently in time and/or on a reduced spatial grid. The former can lead to a lag in the diurnal cycle of surface temperature, while the latter can lead to large surface temperature errors at coastal land points due to surface fluxes computed over the ocean being used where the skin temperature a...

This study investigates the relative role of land surface schemes (LSS) in Weather Research and Forecasting (WRF) model, Version 4, to simulate heat wave events Karachi, Pakistan during 16–23 May 2018. The efficiency WRF model was evaluated forecasting over Karachi using three different LSS, namely NOAH, NOAH-MP, RUC. In addition this we have used longwave (RRTM) shortwave (Dudhia) all schemes....

Estimating the impact of radiation transport through cloud sides on the global energy budget is hampered by the lack of a fast radiation scheme suitable for use in global atmospheric models that can represent these effects in both the shortwave and longwave. This two-part paper describes the development of such a scheme, which we refer to as the Speedy Algorithm for Radiative Transfer through C...